Add path to export-page (#39893)

Adds a missing tag in the trace-to-tree helper that allows you to see the path of the `export-page` span.


## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `pnpm lint`
- [ ] The examples guidelines are followed from [our contributing doc](https://github.com/vercel/next.js/blob/canary/contributing.md#adding-examples)

scripts/trace-to-tree.mjs

@@ -127,6 +127,9 @@ const formatEvent = (event) => {
     case 'hot-reloader':
       head = `${chalk.bold.green(`hot reloader`)}`
       break
+    case 'export-page':
+      head = `${event.name} ${event.tags.path}  ${formatTimes(event)}`
+      break
     default:
       if (event.name.startsWith('build-module-')) {
         const { mergedChildren, childrenTimings, packageName } = event